Double pulse tests can be used to determine the operating characteristics of a power semiconductor. A typical inductor with a magnetic core is used as a current source to the power semiconductor. A magnetic core inductor can realize a high inductance easily; however, it has some drawbacks, e.g., (1) its inductance varies with the current level and (2) it can even be saturated at a higher current. Switching loss evaluation using a double pulse test usually requires a wide range of current levels (e.g. 1 A to 1000 A), therefore, an inductor with a magnetic core is not an ideal candidate for this application.